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Qt 5.4 QTcpServer listening on IPv6 only

  • Hello,

    We have a network server based on Qt 5.4 QTcpServer and listen via:

    ipcServer.listen(QHostAddress::Any, 33000);

    When I build and execute this application on a linux platform, "netstat -ln --tcp" shows:

    tcp6 0 0 :::33000 :::* LISTEN

    There is no listening IPv4 socket, and connection with an IPv4 restricted client fails. Loosening the restrictions on the client to allow an IPv6 connection allows successful connection with the server.

    I'm starting investigations on a win7 platform now, and will post an update when data is available.

    Can anyone explain why this listen doesn't open a listening port on both IPv6 and IPv4?

    Thank You...


  • Hi and welcome to devnet

    Sounds really strange and doesn ot make sense.
    Do you have a special linux build?
    And from where did you Qt install?

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